Those who find evolution convincing need to rethink it a lot more carefully because the evidence is really not there to the extent you think it is. I suspect you are accepting as evidence all sorts of assumptions, speculations and hypotheses that are not evidence, and are taking most of it on faith in spite of yourself.

Saturday, March 10, 2012

Speciation + Evolution = LOTS of Trait Diversity with LOSS of Genetic Diversity leading to end of ability to evolve

"Why don't creationists understand evolution -- it is so simple," the evolutionist wails:

1. Evolution - the change in hereditary traits in populations from generation to generation - is an observed and documented fact, a process that occurs constantly in the natural world around us, and

2. Speciation - the division of parent populations into reproductively isolated daughter populations - is also an observed and documented fact, a process that occurs frequently in the natural world around us.

These two simple processes are sufficient to explain the diversity of life we know, from the world around us, from history, from prehistory and archeology, from geology and physics and paleontology and the fossil record, and from chemistry and the genetic record.

Well, it sounds good on paper, I guess, as theory at least, but unfortunately it fails in reality. Yes, there is an "evolution" by which heritable traits change from generation to generation, but this has never been observed beyond what we call "micro" evolution, or evolution within the genetic limits that define each species, and in fact it can't occur beyond microevolution for the reasons I've given over and over here, which are the same reasons there is no evolution beyond speciation. And yes, speciation is also a documentable fact, but it always occurs with loss of genetic diversity, even to the extreme of fixed loci or total homozygosity for some traits in the population, which makes further evolution beyond speciation purely a pipe dream.

But RAZD just goes on asserting the theory, the pipe dream, as if it were reality, as they all do.

We can even see how evolution causes speciation with Ring Species:

1. the species forms a band made up of several varieties around some barrier to their survival ability,

2. each of the varieties has slightly different hereditary traits from their neighbors,

3. each reproduces with their neighbors in hybrid zones that show a mixing of the hereditary traits of the two neighbors, except that

4. when they meet on the other side of the barrier, the two ends do not mate.

Evolution results in different hereditary traits developing in each of the areas dominated by the different varieties, differences that do not hinder mating until they reach a certain threshold - the difference between the end varieties.

Yes, pretty much but as long as he sticks to the level of traits -- of the phenotypes, of the different observable characteristics between the populations -- he misses the reason what happens happens: The splitting of the populations changes the gene frequencies. When new traits emerge this is because alleles for competing traits have been reduced which can proceed after many population splits to the point that they are completely lost to the new population. After a series of splits the genetic diversity may be quite drastically reduced, and the main reason there is no interbreeding between the first and last populations is the genetic incompatibility that has developed by then.

Again, my prediction is that if you sampled the DNA of the first and last populations (better done in a laboratory where you can sample the first before it too undergoes change), you should find much greater genetic diversity in the first and much reduced diversity in the last, more heterozygosity in the first, more homozygosity in the last, particularly for the traits that are most characteristic of the populations.

Remove any one of the intermediate varieties, so that the band is broken, and you have two distinct species.

We now have more species than before, so life is more diverse. It is so simple:

Evolution + Speciation = Diversity

Way TOO simple, RAZD. Yes you do have more diversity of TRAITS, but you are simultaneously getting REDUCED diversity of GENETIC POSSIBILITIES. This is all just the usual evolutionist daydream based on surface facts completely ignoring what is going on genetically, which is the NECESSARY reduction of genetic diversity, which occurs with EACH splitting off of a portion of the population to form a new population. This is a trend that can keep producing new phenotypes for some time by losing more alleles, but can ultimately arrive at such genetic depletion that no further phenotypic change is possible, a condition like that of the cheetah. Not that this degree of depletion is inevitable, but reduction in that direction certainly is.

This little scenario depicts, I believe, the state of many debates between creationists - people that predominantly use faith to understand the world - and "evolutionists" - people that predominantly use science to understand the world.

What "this little scenario" actually depicts is evolutionist reliance on wishful thinking as they spell out what they THINK happens, because they haven't really faced the GENETIC PICTURE which is working against their all-too-sanguine expectation that change in traits can just go on and on without genetic cost. It really is a daydream, a fantasy. And it's quite the joke that they are constantly claiming to appeal to EVIDENCE and accusing creationists of relying only on faith.

(I skipped his caricature of the creationist response to the above because it is a distraction from what I'm trying to say here.)

Where does "large" change come from? - the change that makes giraffes so different from kangaroos? Simple:

Speciation - the division of parent populations into reproductively isolated daughter populations - is also an observed and documented fact, a process that occurs frequently in the natural world around us, and

Evolution- the change in hereditary traits in populations from generation to generation - is an observed and documented fact, a process that occurs constantly in the natural world around us.

SO simple as long as he just goes on daydreaming about the surface traits and imagining that there are no limits to change.

Speciation + Evolution = More DiversityAfter speciation has occurred, the daughter populations no longer share genes through reproduction, and they are free to evolve completely different traits.

Yes, and this lack of sharing of genes means a LOSS OF GENETIC DIVERSITY. Yes, they ARE "free to evolve copletely different traits" but this is ALWAYS made possible by the loss of competing alleles for those traits, which is completely ignored by evolutionists. You can always get new traits BY LOSING competing alleles, but if the population splits that bring this about continue to occur, eventually a point will be reached where you can't get new traits any more because you'll be completely out of alleles. Speciation may not always mean genetic depletion but it certainly means genetic reduction from earlier populations particularly where the main new traits are emerging.

The likelyhood is high that one of them will become quite different, either to inhabit a new ecology that the other is not as well suited to (could have caused the original split), or to make use of the existing ecology in a different way, and this will lessen competition between the two species rather than drive one to extinction.

Lotta sheer conjecture there. It really isn't even necessary to posit environmental or situational reasons for trait changes or even the population splits themselves. Migration will bring about splits and the splits alone will bring about trait changes. The fewer individuals at the start of a new population the bigger the observable trait changes, the ecology is not likely to have much to do with it. It may be that both populations still have sufficient genetic variability even to undergo several further splits if necessary, but since he's completely ignored the whole question of what happens to the genes while focusing on the traits and fantasizing endless change he's going to miss the state of genetic depletion also when it does finally occur after more population splits.

Continued evolution of daughter populations along different ecological paths results in increased diversity - difference - between them over time. That is how the small amount of difference we seen below can become the amount of difference we see between other bird species.

Again, overrated influence from the environment but this is really a side issue, but anyway, the increased diversity is completely the result of the change in gene frequencies brought about by the population split. If the environment contributes an influence that further impacts the population numbers or reproductive isolation and therefore the gene frequencies, then it will contribute to the trait differences between the populations as well, but again, there is no need for this to happen in order for even great differences to come about as the change in gene frequencies alone will do it.

Continued evolution causes more change - in each population, from generation to generation to generation

Along with change in gene frequencies which can rapidly reduce and even eliminate some alleles as the changes continue, to the point that you run out of alleles for enough traits that further change is impossible, probably a very interesting new population with new traits but no more genetic variability.

That should be enough for starters. There is more to discuss about where change occurs, but this is long enough for now. This thread is about evolution after speciation.

A total pipe dream I'm afraid, as speciation is most likely to occur at the very outer edges of the genetic variability of the species, thus preventing further evolution.

Post a Comment

2 Peter 3:3-7 Knowing this first, that there shall come in the last days scoffers, walking after their own lusts, And saying, Where is the promise of his coming? for since the fathers fell asleep, all things continue as [they were] from the beginning of the creation. For this they willingly are ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water. Whereby the world that then was, being overflowed with water, perished: But the heavens and the earth, which are now, by the same word are kept in store, reserved unto fire against the day of judgment and perdition of ungodly men.

MOST IMPORTANT BLOG POSTS

There's something very wrong with the thinking of a Christian who is more worried about being "fooled by God" in an erroneous judgment about, say, a radiometric dating conclusion than he is about being "fooled by God" in the Bible, very wrong because Christians supposedly believe the Bible to be inspired by God, but science is done by fallible human beings.===========================

You want me to respect science. How can I respect Geology when it accepts the idea that a worldwide stack of different kinds of sedimentary rock represents different time periods of millions of years each, and that the bazillions of catastrophically tossed and tumbled dead things contained in them, often in batches of their own kind, represent particular life forms that lived in each "time" period -- all while smugly proclaiming "there is no evidence" for a global Flood. This is so stupid it is amazing that it was ever entertained, but there it is, today's Dogma of Geology. I'm sure they do solid science in spite of it of course, kind of around and under and between it.

EVOLUTIONISM IS A STRONGHOLD TO BE SPIRITUALLY TOPPLED

2 Corinthians 10:3-5 For though we walk in the flesh, we do not war after the flesh: (For the weapons of our warfare are not carnal, but mighty through God to the pulling down of strong holds;) Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ;

PRAY IT DOWN!

About This Blog

What I want to do here is try to do my best job of stating my own favorite arguments against evolution. There are a couple I think really, logically speaking, ought to bring the whole system crashing down but of course it isn't that easy, human stubbornness being what it is.

There's the geological argument which is basically that you can see with your naked eyes that this world once went through a global Flood, as the Bible reports. That takes care all by itself of the whole Old Earth theorizing that evolution depends on.

And there's the biological argument: It is known that genes DON'T increase although evolution depends on increase. The MORE evolved a species the LESS genetic capacity to evolve it actually has. Breeders certainly know this; and conservationists also know this because genetic depletion in highly specialized species (such as the cheetah) makes them vulnerable to extinction rather than candidates for further variation.

I hope to post on these and other arguments as time permits.

==========================

Ah heck, Mr. Dawkins, we CAN TOO imagine macroevolution by natural selection, same as you can. We can follow out the same Rube-Goldberg sequence of improbable events, acting in a homologically graded series of imaginatively fleshed-out fossils, events that have never been observed in living reality, to the same preconceived conclusion you come to. Our problem is that we know it flies in the face of probability, reason, logic and any other law of rational inquiry and science that may exist, AND that there is no evidence for it, whereas design OBVIOUSLY implies a designer -- obviously, intuitively, rationally, logically, reasonably and probabilistically -- and I'd add "absolutely" if I could get away with it.

========================

Thinking about the implications of the Biblical creation can sometimes draw you close to God in a way that has to be described as worship. That's the main reason for doing it I think.

IT ISN'T FOR LACK OF EXPOSURE TO SCIENCE

A description of my own experience in answer to the usual denigrating assumption that creationism requires ignorance of science -- not that I claim any scientific sophistication of course, merely a basic understanding of some basic facts and principles.Before I became a Christian I absorbed a lot of the thinking about evolution and tried my best to understand it. Even then I was often frustrated thatevidence trails could just about never be found or followed out to any kind of certainty and I found that I always had to give up trying to follow them and just take the conclusions of the scientists pretty much on faith.I definitely had an interest in understanding evolution. I believed in it; I wanted also to understand it, but I found my desire thwarted by the lack of evidence. Iread the Origin of Species, I read lots of stuff by Stephen Jay Gould, very entertaining stuff, I read Skeptical Inquiry regularly, and so on. I investigated the science claims for evolution about as far as the average intelligent non-scientist can be expected to.

It was only after I became a Christian that I got into studying the creationist answers and took seriously my earlier experience offrustration with the lack of evidence for evolution.I strongly wish that those who find it convincing would rethink it a lot more carefully because the evidence is really not there to the extent you think it is, I suspect you are accepting as evidence all sorts of clever speculations that are not evidence, and are taking most of it on faith in spite of yourself.